C.
(I’m pretty sure but if I’m wrong I apologize in advance)
Hello.
First of all, let the number be t.
8 times t can be written like this:

Notice that the number is before the variable and the times sign (×) is not there.
We can write it as 8×t, but we usually write it as 8t.
The sum of means we add:
8t+21
Now, "less than" is "<" :

Therefore, the answer is

I hope it helps.
Have a nice day.

Answer:
B
Step-by-step explanation:
The maximum amount Eric can spend on magazines is $25 less the cost of lunch, $15.
The appropriate inequality sign would be less than since he cannot spend more than $25.
Also, the amount he can spend on magazines would be what is left after paying for lunch.
So the correct inequality is 4m - 15 < 25